A series of seco-A-pentacyclic triterpenoids-3,4-lactone were synthesized and the anti-HBV activities were evaluated in vitro. Several compounds inhibited the secretion of HBV antigen and the replication of HBV DNA in micromolar level. Compounds D7 and D10, seco-A-oleanane-3,4-lactone, suppressed the HBeAg secretion with IC50 values of 0.14 mu M and 0.86 mu M respectively, and the inhibitory activities were also confirmed by detecting the fluorescence intensity of FITC-labeled monoclonal mouse HBeAg antibody via flow cytometry. Compounds D7 and D10 as well as B4, ring-A cleaved 3,30-dioic acid, also displayed remarkable inhibition on both HBV DNA replication at the concentration of 25 mu M and HBV cccDNA (covalently closed circularDNA) replication with IC50 values of 33.5 mu M, 32.7 mu M and 12.3 mu M respectively. (C) 2018 Elsevier Ltd. All rights reserved.
Synthesis and Biological Evaluation of Oleanolic Acid Derivatives As Inhibitors of Protein Tyrosine Phosphatase 1B
Proteintyrosinephosphatase1B (PTP1B) is a negative regulator in the process of insulin signaling and a promising drug target for diabetes and obesity. Derivatives of oleanolic acid were synthesized and evaluated as PTP1B inhibitors. Several derivatives exhibited moderate to good inhibitory activities against PTP1B, with 25f displaying the most promising inhibition (IC50 = 3.12 μM). Structure−activity